High security loud speaker baffle

ABSTRACT

A high security loud speaker baffle for use in institutions such as prisons and the like to resist vandalism. The baffle is comprised of a pair of concave castings constituting a hollow baffle receiving a loud speaker. Each of the castings has a rim portion, one of which is exterior and the other interior, interfitting with one another and butting against shoulders. The two interfitted concave castings can be supported within a cradle receiving the rim portion and connected by tamper-proof screws to resist removal. The hollow loud speaker baffle comprised of the interfitted concave castings in addition to being used as a bidirectional baffle with the cradle can be simply employed by connecting one of the castings directly to a wall surface to provide a unidirectional baffle.

0 I United States Patent 1 [111 3,731,760 Hammes [451 May 8, 1973 [54]HIGH SECURITY LOUD SPEAKER 2,949,163 8/1960 Friedman ..I8l/3l 'B BAFFLEPrimary ExaminerStephen J. Tomsky [75] Inventor. Josef J. l-lammes, St.Louis, Mo. Atmmey Glenn K Robbins [73] Assignee: Lowe ManufacturingCompany, St.

Louis, Mo. [57] ABSTRACT [22] Filed: Dec. 16, 1971 A high security loudspeaker baffle for use in institutions such as prisons and the like toresist vandalism. [21] Appl' 208779 The baffle is comprised of a pair ofconcave castings constituting a hollow baffle receiving a loud speaker.52 us. or. ..1s1/31 B, 206/15, 220/18, Each of the Castings has a rim pone of which is 248/203 exterior and the other interior, interfittingwith one 51 Int. c|...- ..G10k 13/00 H04r 1/28 another and buttingagainst Shwlders- The [58] Field of Search l l 181/31 B 31 fittedconcave castings can be supported within a cra- 'EI 2418/2023 dlereceiving the rim portion and connected by tamper-proof screws to resistremoval. The hollow loud speaker baffle comprised of the interfittedcon- [56] References Cited cave castings in addition to being used as aUNITED STATES PATENTS bidirectional baffle with the cradle can be simplyem- I ployed by connecting one of the castings directly to a 2,718,9319/1955 Boudouns ..l8ll3l B l surface to provide a unidirectional f2,821,260 l/l958 Shaffer 2,829,728 4/1958 Brown ..181/31 B 9 Claims, 19Drawing Figures Patented May 8, 1973 2 SheetsSheet 1 Patented May 8,1973 3,731,760

2 Sheets-Sheet 2 -54 figja HIGH SECURITY LOUD SPEAKER BAFFLE SUMMARY OFTHE INVENTION In the past various types of institutional loud speakerbaffles have been employed. These have been both unidirectional formounting directly to a wall or bidirectional for mounting upon a cradle.The problem has always existed to provide a high degree of security toresist vandalism.

By means of the instant invention there has been provided a strong,durable, rugged, and simply installed high security loud speaker bafflewhich can be employed both as a bidirectional baffle with a speciallydesigned cradle or as a unidirectional baffle for mounting directly upona wall surface.

The high security loud speaker baffle of this invention is comprised ofa pair of concave castings each having a peripheral rim portion. The rimportions are specially designed so that one is an exterior portion andthe other casting has an interior rim portion, which portions interfitand abut against shoulders. The rim portions are raised and are seatedwithin a specially designed cradle with aflixation being provided fromthe interior of the cradle. The cradle is adapted to be connected to ajunction box or mounting box by tamper proof screws. In the installationof the baffle, a loud speaker can first be connected to one of theconcave castings with the connecting wire being interfitted through ahole, and the other casting then affixed to the first, the wiring beingaccommodated in the second casting by means of a notch in the rim thatregisters with the hole in the first casting.

The loud speaker baffle may also be simply connected to a wall surfaceto provide a unidirectional baffle without the use of a cradle. This isaccomplished by affixing one of the concave castings directly to themounting box or other base on the wall surface and then simplyconnecting the other half of the loud speaker baffle constituting themating concave casting.

The above features are objects of this invention and other objects willappear in the detailed description which follows and will be otherwiseapparent to those skilled in the art.

For the purpose of example there is shown in the accompanying drawings apreferred embodiment of this invention. It is to be understood thatthese drawings are for the purpose of illustration only and that theinvention is not limited thereto.

In the drawings:

FIG. 1 is a view in front elevation of the cradle mounted baffle.

FIG. 2 is a view in side elevation thereof.

FIG. 3 is a view in rear elevation of the cradle mounted baffle.

FIG. 4 is an enlarged view in section taken on the line 4-4 of FIG. 1.

FIG. 5 is an enlarged view in section taken on the line 5-5 of FIG. 1.

FIG. 6 is a fragmentary plan view of the front baffle showing theperforated screen holes.

FIG. 7 is an enlarged view in section taken on the line 7-7 of FIG. 6showing the connection of the screen.

FIG. 8 is a top plan view partially broken away of the mounting orjunction box.

FIG. 9 is a view in side elevation partially broken away of the mountingor junction box.

FIG. 10 is a bottom plan view of the cradle.

FIG. 11 is a view in section taken on the line ll-l1 of FIG. 10.

FIG. 12 is a top plan view of the cradle.

FIG. 13 is a fragmentary plan view of a specialized tool used for thesecurity screws.

FIG. 14 is a view in end elevation taken from the right hand of the toolof FIG. 13.

FIG. 15 is a fragmentary exploded view in axial cross-section showingthe interfitting of the front and rear baffles.

FIG. 16 is a fragmentary exploded plan view showing the interfitting ofthe front and rear baffles.

FIG. 17 is a plan view showing the unidirectional mounting of the baffleto a wall.

FIG. 18 is a view in side elevation of the mounted baffle of FIG. 17partially broken away in section.

FIG. 19 is a view in section taken on the line 19-19 of FIG. 18.

DESCRIPTION OF THE INVENTION The loud speaker baffle of this inventionis generally identified by reference numeral 20 in FIGS. 1 through 4. Asthere shown, it is connected to a specially designed cradle22 affixed toa ceiling 24 through a mounting box 26 to provide for bidirectionalemanation of sound waves from a conventional loud speaker 28 mountedwithin the loud speaker baffle.

The loud speaker baffle 20 is comprised of a front baffle housing 30 anda rear baffle housing 32. The front housing 30 is formed of a generallydish shaped or concave casting of aluminum or other metal to provide arectangular protective grid 34. A rim 36 protrudes from the exterior ofthe casting for better seating within the cradle as will be described.The rim 36 of the front casting is formed as an exterior rim to interfitwith the interior rim 38 of the rear casting. The rim 36 has an interiorshoulder 40 and a' square end 42 to provide for mating and seating withthe shoulder 44 and the square end 46 of the interior rimof the rearbaffle. At the bottom of the baffle rim portions as best shown in FIG. 4registering holes are provided in the exterior and interior rimsdesignated by the reference numeral 48 to receive a tamper-proof screw50 to connect the baffles together.

The front baffle rim at the top has an opening 52 to receive a wire forconnection of the loud speaker which in the assembly of the housingmaybe first connected to the front portion of the baffle. The matingportion of the interior rim 38 of the rear baffle as best shown in FIG.15 and 16' is provided with a notch 54 to receive the connecting wire(not shown) in the installation.

The front baffle as shown in FIG. 4 is provided with openings 56 in theface of the casting to receive additional tamper proof screws 57 foraffixation of a perforated metallic screen 58. The rear baffle isprovided with threaded studs 60 integrally formed with the interior ofthe rear baffle casting to receive a perforated metallic screen 62. Boththe screens 58 and 62 can be conventionally secured in place byTinnerman nuts 64.

The cradle 22 is comprised of a rectangular box-like base 68 providedwith openings 70 at the end for affixation to the junction box 26.The'affixation is provided by tamper-proof bolts 72. Supported upon thebase 68 is an arcuate cradle 76 which has a central groove 78 receivingthe exterior rim 36 of the front baffle when the front and rear baffleare connected together as shown in FIG. 4. An opening 80 is provided inthe central portion of the cradle and the groove to receive anelectrical lead wire and additional openings 82 are provided at theopposite ends of the cradle for reception of bolts 84vadapted to connectthe baffle to the cradle as best shown in FIG. 4.

The junction box 26 is best shown in FIGS. 4, 5, 8, and 9. It is abox-like structure having a base 86 and end walls 88 and side walls 90.A central Opening 92 is provided for the loud speaker electricalconnecting wire. Openings 94 are additionally provided in the base forconnecting the box to the ceiling or wall through screws 96 as shown inFIG. 4. Threaded openings 98 are provided in the ends for reception ofthe tamperproof bolts fitting through the registering openings in theends of the base of the cradle as shown in FIG. 5.

The tamper-proof screws used to prevent unathorized tampering are shownin FIGS. 6 and 7. They may take the form of either a screw or a bolt andare provided with a fiat beveled head having a pair of openings 100instead of the usual diametrical slot. The openings 100 are adapted tobe engaged by a specially designed tamper-proof screw driver shown inFIGS. 13 and 14 and identified by the reference numeral 102. This screwdriver with a conventional handle (not shown) and a pair of prongs 104at the end which are received by the openings 100 in the heads of thetamper proof screws and it is apparent that the screws or bolts can bethreaded only by the use of the specially designed tamper-proof screwdriver as shown.

The use of the loud speaker baffle 20 of this invention has been shownin FIGS. 1 through 4 with the eradle 22 for bidirectional generation ofsound waves from the loud speaker 28 through both the associated gridsand screens in the front and rear baffle castings. A modified use of theloud speaker baffle for unidirectional employment by direct mounting ofthe baffle upon a vertical wall surface 110 is shown in FIGS. 17 through19. In this employment the cradle is not required to be used and theloud speaker baffle can be directly mounted to the wall by theconnecting screws 1112 passing through the openings 56 in the frontbaffle. In this modification, the screen 58 is not required to be usedand the loud speaker 28 may be mounted either to the front baffle asshown in FIG. 4 or to the rear baffle upon the threaded studs 60. In theunidirectional employment of the mofidication shown in FIG. 17 through19, it will be understood that the lead wire opening 52 in the frontbaffle is plugged. The conventional lead wire for the connection of theloud speaker can be passed through the wall by passing it through thegrid openings and the grid of the front baffle casting.

USE

tion box itself. The rear baffle casting 32 is then interfitted with thefront baffle casting in the relationship shown in FIGS. 15 and 16 withthe exterior rim 36 of the front baffle fitting over the interior rim 38of the rear baffle and with the notch 54 of the rear baffle registeringwith the opening 52 of the front baffle. The tamper-proof screw 50 isthen fastened through the registering openings in the interfitting rimsof the baffle castings as shown at the bottom of FIG. 4 through the useof the specially designed tamper-proof screw driver 102. It will beunderstood that other types of tamperproof screws and screw drivers canbe used as desired as these are conventional in the art.

With the baffle castings connected together the bolts 84 are fittedthrough the openings 82 at the interior of the cradle and at theopposite ends to affix both the front and the rear baffle firmly to thecradle. Only two such bolts are required with one each being used on thefront and rear baffles rims at opposite sides of the cradle. The cradlegroove prevents twisting. The raised rim of the front baffle nestswithin the groove 78 and provides a secure interfit to resist any heavyblows caused by vandalism and the like.

With the baffle castings connected to the cradle, the cradle is theninterfitted over the junction box in the relationship shown in FIG. 4and the tamper proof screws 72 are inter-fitted in the registering holesat the ends of the base of the cradle and the junction box to completethe connection.

For the modification shown in FIGS. 17 through 19 for a unidirectionalapplication, the cradle 22 is not employed. In this modification, thefront baffle is used for a direct connection to the wall or aconventional junction box as desired. The loud speaker baffle may beconnected either in the fashion shown in FIG. 4 to the front baffle orwhere desired may be connected to the rear baffle which in a change ofrelationship is actually used as a front baffle for the unidirectionalapplication.

Various changes and modifications may be made within this invention aswill be readily apparent to those skilled in the art. Such changes andmodifications are within the scope and teaching of this invention asdefined by the claims appended hereto.

What is claimed is:

1. In a high security loud speaker baffleenclosure: fir a d. e n b wkl kMu in p rt sm a having a rim, the rim of one telescoping into the rim ofthe other, whereby when the housing portions are te stq her. 1192idntlxf rm t n losure. the rim portion of at least one housing portionextending outwardly from the periphery of the enclosure providing aridge; the rims being of rigid material and the t sc pi bein t i b tatiatwidth to esis 5.69amtionof the parts by noncoaxial warping; at leastone housing portion having an openwork grill that cannot be removed fromthe outside of the housing portion, so that a loudspeakerwithin theenclosure of the housings may be protected; tamper-proof means to holdthe housing portions together with their rims telescoped, including acradle engageable onto the rim of the conjoined housing portions, thecradle having a recess means complementary to the ridge on the onehousing portion, and means to secure the enclosure to the cradle fihnlysothatKh e eiieldsacarihei be twisted with respect to the cradle.

2. In the baffle enclosure of claim 1, the telescoping rims both havingprojections forming at least one peripheral ridge and providing ridgewalls facing oppositely, the cradle having its recess means shapedcomplementary to both ridge walls so that both ridge walls cooperate inresisting twisting.

1 in the baifi'lebfclaiid Lapin 'likeeleinent of the tamper-proof meansbeing located opposite the cradle and joining the telescoping rims.

4. In the baffle 6? claim 1, the cradle comprising a hollow member, andtamper-proof means attaching elements inside the cradle, one extendinginto each housing element and affixing it to the cradle.

prevent twisting of the housing in the cradle.

7; Ifi't'h'bafile aretatifiieihz'eiaaizsenig' 'hoilow and having wallsoutwardly projecting from the housing, a bracket attachable to the walland fitted within the said walls to be concealed by them, andtamperproof connectors between the cradle and the bracket.

'8'. iii the bafilebfilairfi"iTtfibpenii drlZgiilI having relativelylarge-openings, and a screen back-up in the housing back of the grill.

9. In the baffle of claim 1: both housings having openwork grills, andopenings through one housing member to receive screws or the like forfastening it directly to a wall or like support.

1. In a high security loud speaker baffle: a first and a second housingportions each having a rim, and the rim of one telescoping into the rimof the other providing a close fit and the parts being of rigid materialand the telescoping being of substantial width to resist warpingseparation of the parts; at least one housing portion having an openworkgrill that cannot be removed from outside the housing portions, so thata speaker within the housings may be protected; and tamper-proof meansto hold the housing portions together with their rims telescoped,including at least one pin-like element passing through the telescopedrims.
 2. In the baffle of claim 1: the tamper-proof means including acradle to be secured to a wall or the like, and means contained withinthe cradle for securing the two housing portions together at one side,the said contained means being inaccessible to the exterior of theassembly when the cradle is secured to the walls.
 3. In the baffle ofclaim 2, the pin-like element of the tamper-proof means being locatedopposite the cradle.
 4. In the baffle of claim 2, the cradle comprisinga hollow member, and the tamper-proof means including attaching elementsinside the cradle, one extending into each housing element and affixingit to the cradle.
 5. In the baffle of claim 2, the housing portionshaving a projecting rim, and the cradle having a recess complementary tothe rim, so that twisting of the housing assembly in the cradle isprevented.
 6. In the baffle of claim 2: the cradle and telescoping rimsof the housings having cut-outs contained within the cradle so as to beinaccessible from outside the cradle, for admitting electric wiring intothe baffle.
 7. In the baffle of claim 2: the housing being round andhaving a medial projection around it, the cradle having an arcuateportion to receive the round housing, and a recess complementary to theprojection, to prevent twisting of the housing in the cradle.
 8. In thebaffle of claim 2: the cradle being hollow and having walls outwardlyprojecting from the housing, a bracket attachable to the wall and fittedwithin the said walls to be concealed by them, and tamper-proofconnectors between the cradle and the bracket.
 9. In the baffle of claim1: the openwork grill having relatively large openings, and a screenback-up in the housing back of the grill.
 10. In the baffle of claim 1:both housings having openwork grills, and openings through one housingmember to receive screws or the like for fastening it directly to a wallor like support.